Transcript Slide 1
1. What have you learned from this workshop? 2. Where do you see the field going in the next 5 years? 3. Which projects would be most interesting as a graduate student thesis? Learn? Moi? • The field is young and vibrant • This proves there is much to learn! And hope. • Clusters, dSph, & halo field subdwarfs are the 3 old metal-poor cospatial populations. How are/are they related? This remains unclear. [later star formation in dSph is perhaps a separate problem] • There are clear structural/dynamical/DM differences between dSph and clusters different formation? • Do metal-poor GC’s trace PoPII? [Redefine Sn] • Formation Models are developing extremely impressively: now good enough they can be used as a research tool, to investigate what we don’t yet know. This is a huge advance. Very impressive. • But: still very much post-diction recipes to reproduce data, not yet an investigation of parameter space. Is there any `if this is wrong something important must be changed’ prediction? Comments of my colleagues For a model to be science, it must make falsifiable predictions. Do they? All these models tell me to relax, since all galaxy formation problems are solved. Since all models differ, no wonder I’m suspicious Things are seen as they are since this is the best understood of all possible worlds Modulo variance. And physics. Of course galaxy formation models are correct. They have always been correct. Just different than they used to be. Models should be used to isolate and investigate what we do not understand, not provide post hoc recipes to postdict data. Next few years Gaia will revolutionise the subject: Launch 12/2011 Get ready to handle complex 3-D dynamical data… `complete’ the dwarf census – help a wee bit only? Quantify inner galaxy better: we focus on the outer galaxy since we can, not because it is most significant. The reverse may be true: where are most stars? Most angular momentum? Most metals? More dynamics 1:– resolve core-cusp finally – probably no surprises, but leaves pre-history (what is `no surprise’????) More dynamics 2: outer parts and tides – is there anything fundamental here? May be relevant for galaxy formation, not to study the nature of dark matter? Model-Building realistic LSB dwarfs?? Uniquely? Understand the dSph orbits – what/where was Sgr 8 Gyr ago? The bigger picture: linking the dSph to formation of the bulge, old thick disk, thin disk, assorted debris,…. Clarify the environment [variance] dependence: loose groups vs clusters What provided pre-enrichment? Re-ionisation? http://www.rssd.esa.int/index.php?project=GAIA&page=index • Several large kinematic studies: now is the time to merge, publish, and make consistent all the data: ----• The CTP manifesto • An AVO-consistent dBase of stars, kinematics, photometry, [spectra?].. for all dSph: we’ll happily be part of this – and do it. the Matt Walker opportunity? Add our echelle spectra too, if wanted • Access for contributors only at first? A few viable problems Can anyone make reliable simulations for a variety of plausibly different [W]DM models*???? Stay topical in LHC era! Is small-scale feedback internal? External? Both? – limited by SFR(t) – [quantify the limits better] & chemical element ratios What `really’ would happen to DM in a baryon-dominated region – is it all evacuated dynamically, creating cores? Or vice versa: is a smooth potential adequate? Star cluster like model? How did – or did? – small DM halos virialise? What is the intermediate phase-mixing state as a star-forming region evaporates into a dIrr/dSph environ (theory/obs) Are there many small DM sub-halos in mid-sized dIrr galaxies (LMC-like) – look for effect on HI/GMC. Whatever caused the pre-enrichment*, might this (set of) processes affect early structures Where did the field halo form its stars? Mixing scale-length limits from element ratio plus dynamics analysis. Why were all progenitors so exactly similar (reionisation)? What is relation to rest of galaxy? Galaxy cluster systems bi-modal in colour (age? Other?). Why bi, not tri? Are most GC systems correlated with old (popII) halo field? Why? Does every galaxy have a metal-poor PopII stellar halo – this would seem to be a non-negotiable test of Lcdm substructure photoionisation models. Does this apply to galaxies of every mass? * this is a harder one…